Carburetor



June 9, 1936. E, L RR A V 2,q43,s95

CARBURET OR Filed Oct. 1, 1934 Patented June 9, 1936 UNITED STATES CARBURETOR Eladio Artufiedo Larrosa, Bilbao, Spain Application October 1, 1934, Serial .No. 746,464 In Spain May 18, 1934 3 Claims. (01. 261-41) fIll-ie present invention relates to improvements in the manufacture of carburetors-for internal :combustion enginesand is characterized by various constructional modifications introduced into this type of apparatus, which notonly simplify its operation and actuation .but also assure reater aefilciency and automatic action, particularly on slow running. These general advantages are a consequence of the various features combined in the apparatus. 1

,Accord-ingto-the present invention there is provided a carburetor .-for internal combustion enines characterized by the fact that a bypass intake is provided in combination with the main intake, and that-the by-pass intake is used instead .of :the main intake when the engine is running idle. Preferably the throttle control of the main intake also controls the by-pass intake, the arrangement being such that, when the main intake is closed, :the :by-pass intake is opened and vice --versa.

the main intake there are preferably provided two or more jets or nozzles, and as a :result a :more homogeneous andv explosive mixture is ,pmducedthan with carburetors used heretofore, and at the same time better acceleration and easier starting is obtained.

In the carburetor according to the present :invention .all levers and .control devices ,for additional air are .omitted, onlytwo controls being used, one for the gases and one for" the air.

Other featuresof the invention will appear from the following specification, and by reference to the attached :drawing, which illustrates :diagrammatically partly in elevation and partly in section, i-a carburetor constructed according to the present invention.

The :carburetorushown .on the drawing comprises the following members.

A body :1, which is attached at its-upper part to the inlet pipe of the engine, and to the lowerpart of which is attached a central tubular member 2, screwed internally thereto-4 This central member 2 is provided at its lower part with a choke member 3, which controls the intake in a fixed manner. Around this central member is disposed a. constant level chamber 5, in the interior of which is disposed the float 4, which perates in known manner. This constant level chamber is held in position against the member I by a sleeve member 6, which is screwed on the member 2. In this member 6 is mounted an air strangler comprising an operating lever 1, provided with fixing means 8 and 9 for an actuating device, and a control shaft I2, to the top of which is fixed the strangler M by means of thescrew l 3. Between the-memberfi and the constant level chamber and around the lower part of the central member 2, there is disposed a packing II for hermetical sealing.

At .the upper part of ,the member l is disposed the throttle 16, mounted upon ashaft I 9 andsecured by ,a fixing screw 15. To one end of the shaft .l9is secured the operating lever 10 fixed by a screw 20. At the opposite end, the shaft is supported by a member 22, screwed-into the body I and hollow in the direction of its axis, this hollow portion forming a passage which extends tlgrough the part acting as a support for the shaft Screwed into the free end of the member 22 is a screw 2| terminating in a needlepoint and axially bored in such a manner that it enables air to pass therethrough towards the passage formed in the axis of member 22, andat the same time forms a needle valve for closing the. said formed in the member 22 and the lower part of which extends into the interior of the petrol filling ,of the float chamber-and terminates in a jet l8 or jets. In the throttle I6 andshaf t IS an opening 23 is formed,'which coincides withthe passage formed in the member 22 when the ;po- -sition of the shaft I9 is such that mixture ,is cut off by the throttle.

Finally, within the member 2 there are disposed two or more passages terminating in jets I8a, which open into the main intake pipe of the carburetor, in the interior of the member 2. The operating of the device above described is a follow .V For starting, the throttle arrangement 16 is left -,partiall-y open and the air strangler l4 is closed,

whereby directly above the jets I80. suction is established which will form a requisite carburetted mixture and consequently cause the initial explosion to take place with the greatest rapidity and certainty. Once the ability of the engine to run is established the Strangler I4 is opened according to the capacity of the jet or jets disposed at itslower end. The petrol intake thus established may be modified by the control exer- 'cised by the control screw 2|, which at the same time permits air to enter through its central bore,

said air mixingwith the petrol which has been 7 lifted up. Thus the amount ofpetrol may be adjusted according to whether the amount of air entering is larger or smaller, until the minimum petrol consumption necessaryfor the running of the engine with a minimum number of 'revolu-' tions is reached.

' the engine.

' When acceleration is started and the throttle I6 is opened the engine will develop an energetic suction, which will be exerted 'directly'up'on the jets I8a disposed in the member 2,,and simul 'taneously, the movementof the throttleshaft will cause the coincidence of theopeningfl with the passage formed in the member 221 to cease,

thereby cutting'off the intake of petrol through the passage ll; Further opening of the strangler will effect the strongest possible intake of air is proportional to the output energy developed by I; The fact that two r more jets Ilia areprovided completely eliminates stoppages of the engine by 7' jet obstruction,- and it may even be considered service station.

that complete, obstruction of all the jets is absolutely impossible. Moreover if one or more of thejets become unserviceable it is only necessary when the engine ceasesto function'normally to slightly close the air 'strangler, and it is still possible at a reduced speed, to reachthe nearest lit is to beund'erst oo'dthat the in'ventio n -may undergo modifications inrespect of its general arrangement and the member or members forming it without departing from the scope of the invention as herein ascertained.

1 Iclaimz 1: A "carburetonfor internal combustion enginescomp'rising atubular body, a constant level float chamber beneath said body, a tubular mem-' ber passing through saidchamb'er and secured at its upper end to 1 said tubular body, a sleeve secured to said'tubular member and holding said fioat chamber'in place, said tubular'lbody' and said tubular member and said sleeve constituting a single passage, astrangler located in said sleeve,

a choke member located in said tubular member adjacent the end thereof which is'adjacent said sleeve, fuel ducts each communicating at one end with the fuelchamber and at its'other end with a jet element delivering into saidtubular I member above said choke, a throttle valve in said tubular body, a by-pass [duct from said float V chamber to said throttle valve, an air inlet valve cooperating with said by-pass duct, and meansq governed by said throttle valve for opening said by-pass duct to communicatexwith said tubular body on the suction side of said throttle 'valve when said throttle valve is closed and for shutting oif said by-passwhile said throttle valve is open.

" 2. A carburetor for internal combustion engines," comprising a suction duct having an intake and an outlet end, the latter being adapted for; connection to the intake of an engine, a constant level float chamber surrounding said suction duct, 7 i 1 fuel-ducts and jets to deliver fuel into said suc-r 7 tion duct, a strangler in said suction du'ctadja cent the intake end of the same, andfa throttle' 1 valve'in said' suction'duct adjacent t e outlet end of the same, saidthrottlevalvejincluding a.

shaft having a hollow portion, a supporting mein ber projecting into said hollow portionand hav- 7 ing a passage communicating with ports in: said shaft and throttle valve which deliver'jto the suction side of: said throttle valve 'ahdf'are controlled by the position of saidthrottle 'va1ve,'the

' passage in said supportingmembei' communicating through'aductwith fuelinthe'ifioat chamber,ithe passage of said supporting member also having a portion for communicating with'the atmosphere, and a screw threaded into said'por- 'tionand'formed with an air passageand a needle I point in virtue of which said screw functions as a means to regulate the amount of air'a'nd petrol 'which the engine may aspirate via the support- "ing memberspass'age; .7

' 3. In carburetors'having a fuel reservoir. andgmain and by-pass fuel jets delivering therefrom a 'into a 'passage' which is connectible to the-intake of an internal combustion engine; a throttle valve" in said passage and including a shaft a 'stationary supporting member comprising a bearing; for said shaft, said shaft havinga hollow portion to receive said supporting member, said supporting member having a passage communicat ing; at its outer end with the atmosphere and'at its inner end with a port. that registers with a similar port in said shaft only when said throttle valve is closed, said ports delivering to the suction endof said. passage, aiscre'w-valve in'theouter end of said supporting member's" passage and having a point to act as a valve forsaidE-t -passag e,'said screw-valve having an air passage,

and a by-pass duct: from said fuel chamber to said supporting member's passage entering the same between said fuel valve and saidgscrewvalve, in virtue of which said screw-valve-may be =5 used to regulate the amount of 'airand petrol which the engine may aspirate while idling. r ELADIO AR 'LARROSA. 

